British art dealers are lamenting the enforcement this January of a "droit de suite" which provides artists' heirs - within 70 years of their death - with a percentage of the re-sale price of their work.

The 70-year limit was introduced in 2006, but the UK delayed it until 2012. As much as 60% of art sales may be affected.

Currently, the second largest art market in the world, with an 18% share, the U.K. trails the U.S. in sales. However, some dealers fear that the new tax will cause major business transactions to move more to the U.S. and China.

The new law will affect artists' heirs in future sales with a sliding scale of payments from 4% of the sale price of cheaper items to 0.25% of the most expensive.

A droit de suite bill to provide living artists with resale royalties for auctioned works was introduced last week in the U.S. Congress.

According to The Art Newspaper, the Equity for Visual Artists Act of 2011 would set aside 7% of the price for works resold for more than $10,000 at major auction houses, with half the proceeds going to the artists and half to non-profit art museums.

The U.S. legislation is aimed at public auction houses with "over $25 million in sales the previous year."

Currently, 59 countries (and the state of California) have a droit de suite law.